1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_ELF_H
3 #define _ASM_X86_ELF_H
4
5 /*
6 * ELF register definitions..
7 */
8 #include <linux/thread_info.h>
9
10 #include <asm/ia32.h>
11 #include <asm/ptrace.h>
12 #include <asm/user.h>
13 #include <asm/auxvec.h>
14 #include <asm/fsgsbase.h>
15
16 typedef unsigned long elf_greg_t;
17
18 #define ELF_NGREG (sizeof(struct user_regs_struct) / sizeof(elf_greg_t))
19 typedef elf_greg_t elf_gregset_t[ELF_NGREG];
20
21 typedef struct user_i387_struct elf_fpregset_t;
22
23 #ifdef __i386__
24
25 #define R_386_NONE 0
26 #define R_386_32 1
27 #define R_386_PC32 2
28 #define R_386_GOT32 3
29 #define R_386_PLT32 4
30 #define R_386_COPY 5
31 #define R_386_GLOB_DAT 6
32 #define R_386_JMP_SLOT 7
33 #define R_386_RELATIVE 8
34 #define R_386_GOTOFF 9
35 #define R_386_GOTPC 10
36 #define R_386_NUM 11
37
38 /*
39 * These are used to set parameters in the core dumps.
40 */
41 #define ELF_CLASS ELFCLASS32
42 #define ELF_DATA ELFDATA2LSB
43 #define ELF_ARCH EM_386
44
45 #else
46
47 /* x86-64 relocation types */
48 #define R_X86_64_NONE 0 /* No reloc */
49 #define R_X86_64_64 1 /* Direct 64 bit */
50 #define R_X86_64_PC32 2 /* PC relative 32 bit signed */
51 #define R_X86_64_GOT32 3 /* 32 bit GOT entry */
52 #define R_X86_64_PLT32 4 /* 32 bit PLT address */
53 #define R_X86_64_COPY 5 /* Copy symbol at runtime */
54 #define R_X86_64_GLOB_DAT 6 /* Create GOT entry */
55 #define R_X86_64_JUMP_SLOT 7 /* Create PLT entry */
56 #define R_X86_64_RELATIVE 8 /* Adjust by program base */
57 #define R_X86_64_GOTPCREL 9 /* 32 bit signed pc relative offset to GOT */
58 #define R_X86_64_GOTPCRELX 41
59 #define R_X86_64_REX_GOTPCRELX 42
60 #define R_X86_64_32 10 /* Direct 32 bit zero extended */
61 #define R_X86_64_32S 11 /* Direct 32 bit sign extended */
62 #define R_X86_64_16 12 /* Direct 16 bit zero extended */
63 #define R_X86_64_PC16 13 /* 16 bit sign extended pc relative */
64 #define R_X86_64_8 14 /* Direct 8 bit sign extended */
65 #define R_X86_64_PC8 15 /* 8 bit sign extended pc relative */
66 #define R_X86_64_PC64 24 /* Place relative 64-bit signed */
67
68 /*
69 * These are used to set parameters in the core dumps.
70 */
71 #define ELF_CLASS ELFCLASS64
72 #define ELF_DATA ELFDATA2LSB
73 #define ELF_ARCH EM_X86_64
74
75 #endif
76
77 #include <asm/vdso.h>
78
79 #ifdef CONFIG_X86_64
80 extern unsigned int vdso64_enabled;
81 #endif
82 #if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION)
83 extern unsigned int vdso32_enabled;
84 #endif
85
86 /*
87 * This is used to ensure we don't load something for the wrong architecture.
88 */
89 #define elf_check_arch_ia32(x) \
90 (((x)->e_machine == EM_386) || ((x)->e_machine == EM_486))
91
92 #include <asm/processor.h>
93
94 #ifdef CONFIG_X86_32
95 #include <asm/desc.h>
96
97 #define elf_check_arch(x) elf_check_arch_ia32(x)
98
99 /* SVR4/i386 ABI (pages 3-31, 3-32) says that when the program starts %edx
100 contains a pointer to a function which might be registered using `atexit'.
101 This provides a mean for the dynamic linker to call DT_FINI functions for
102 shared libraries that have been loaded before the code runs.
103
104 A value of 0 tells we have no such handler.
105
106 We might as well make sure everything else is cleared too (except for %esp),
107 just to make things more deterministic.
108 */
109 #define ELF_PLAT_INIT(_r, load_addr) \
110 do { \
111 _r->bx = 0; _r->cx = 0; _r->dx = 0; \
112 _r->si = 0; _r->di = 0; _r->bp = 0; \
113 _r->ax = 0; \
114 } while (0)
115
116 /*
117 * regs is struct pt_regs, pr_reg is elf_gregset_t (which is
118 * now struct_user_regs, they are different)
119 */
120
121 #define ELF_CORE_COPY_REGS(pr_reg, regs) \
122 do { \
123 pr_reg[0] = regs->bx; \
124 pr_reg[1] = regs->cx; \
125 pr_reg[2] = regs->dx; \
126 pr_reg[3] = regs->si; \
127 pr_reg[4] = regs->di; \
128 pr_reg[5] = regs->bp; \
129 pr_reg[6] = regs->ax; \
130 pr_reg[7] = regs->ds; \
131 pr_reg[8] = regs->es; \
132 pr_reg[9] = regs->fs; \
133 savesegment(gs, pr_reg[10]); \
134 pr_reg[11] = regs->orig_ax; \
135 pr_reg[12] = regs->ip; \
136 pr_reg[13] = regs->cs; \
137 pr_reg[14] = regs->flags; \
138 pr_reg[15] = regs->sp; \
139 pr_reg[16] = regs->ss; \
140 } while (0);
141
142 #define ELF_PLATFORM (utsname()->machine)
143 #define set_personality_64bit() do { } while (0)
144
145 #else /* CONFIG_X86_32 */
146
147 /*
148 * This is used to ensure we don't load something for the wrong architecture.
149 */
150 #define elf_check_arch(x) \
151 ((x)->e_machine == EM_X86_64)
152
153 #define compat_elf_check_arch(x) \
154 ((elf_check_arch_ia32(x) && ia32_enabled_verbose()) || \
155 (IS_ENABLED(CONFIG_X86_X32_ABI) && (x)->e_machine == EM_X86_64))
156
elf_common_init(struct thread_struct * t,struct pt_regs * regs,const u16 ds)157 static inline void elf_common_init(struct thread_struct *t,
158 struct pt_regs *regs, const u16 ds)
159 {
160 /* ax gets execve's return value. */
161 /*regs->ax = */ regs->bx = regs->cx = regs->dx = 0;
162 regs->si = regs->di = regs->bp = 0;
163 regs->r8 = regs->r9 = regs->r10 = regs->r11 = 0;
164 regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0;
165 t->fsbase = t->gsbase = 0;
166 t->fsindex = t->gsindex = 0;
167 t->ds = t->es = ds;
168 }
169
170 #define ELF_PLAT_INIT(_r, load_addr) \
171 elf_common_init(¤t->thread, _r, 0)
172
173 #define COMPAT_ELF_PLAT_INIT(regs, load_addr) \
174 elf_common_init(¤t->thread, regs, __USER_DS)
175
176 void compat_start_thread(struct pt_regs *regs, u32 new_ip, u32 new_sp, bool x32);
177 #define COMPAT_START_THREAD(ex, regs, new_ip, new_sp) \
178 compat_start_thread(regs, new_ip, new_sp, ex->e_machine == EM_X86_64)
179
180 void set_personality_ia32(bool);
181 #define COMPAT_SET_PERSONALITY(ex) \
182 set_personality_ia32((ex).e_machine == EM_X86_64)
183
184 #define COMPAT_ELF_PLATFORM ("i686")
185
186 /*
187 * regs is struct pt_regs, pr_reg is elf_gregset_t (which is
188 * now struct_user_regs, they are different). Assumes current is the process
189 * getting dumped.
190 */
191
192 #define ELF_CORE_COPY_REGS(pr_reg, regs) \
193 do { \
194 unsigned v; \
195 (pr_reg)[0] = (regs)->r15; \
196 (pr_reg)[1] = (regs)->r14; \
197 (pr_reg)[2] = (regs)->r13; \
198 (pr_reg)[3] = (regs)->r12; \
199 (pr_reg)[4] = (regs)->bp; \
200 (pr_reg)[5] = (regs)->bx; \
201 (pr_reg)[6] = (regs)->r11; \
202 (pr_reg)[7] = (regs)->r10; \
203 (pr_reg)[8] = (regs)->r9; \
204 (pr_reg)[9] = (regs)->r8; \
205 (pr_reg)[10] = (regs)->ax; \
206 (pr_reg)[11] = (regs)->cx; \
207 (pr_reg)[12] = (regs)->dx; \
208 (pr_reg)[13] = (regs)->si; \
209 (pr_reg)[14] = (regs)->di; \
210 (pr_reg)[15] = (regs)->orig_ax; \
211 (pr_reg)[16] = (regs)->ip; \
212 (pr_reg)[17] = (regs)->cs; \
213 (pr_reg)[18] = (regs)->flags; \
214 (pr_reg)[19] = (regs)->sp; \
215 (pr_reg)[20] = (regs)->ss; \
216 (pr_reg)[21] = x86_fsbase_read_cpu(); \
217 (pr_reg)[22] = x86_gsbase_read_cpu_inactive(); \
218 asm("movl %%ds,%0" : "=r" (v)); (pr_reg)[23] = v; \
219 asm("movl %%es,%0" : "=r" (v)); (pr_reg)[24] = v; \
220 asm("movl %%fs,%0" : "=r" (v)); (pr_reg)[25] = v; \
221 asm("movl %%gs,%0" : "=r" (v)); (pr_reg)[26] = v; \
222 } while (0);
223
224 /* I'm not sure if we can use '-' here */
225 #define ELF_PLATFORM ("x86_64")
226 extern void set_personality_64bit(void);
227 extern int force_personality32;
228
229 #endif /* !CONFIG_X86_32 */
230
231 #define CORE_DUMP_USE_REGSET
232 #define ELF_EXEC_PAGESIZE 4096
233
234 /*
235 * This is the base location for PIE (ET_DYN with INTERP) loads. On
236 * 64-bit, this is above 4GB to leave the entire 32-bit address
237 * space open for things that want to use the area for 32-bit pointers.
238 */
239 #define ELF_ET_DYN_BASE (mmap_is_ia32() ? 0x000400000UL : \
240 (DEFAULT_MAP_WINDOW / 3 * 2))
241
242 /* This yields a mask that user programs can use to figure out what
243 instruction set this CPU supports. This could be done in user space,
244 but it's not easy, and we've already done it here. */
245
246 #define ELF_HWCAP (boot_cpu_data.x86_capability[CPUID_1_EDX])
247
248 extern u32 elf_hwcap2;
249
250 /*
251 * HWCAP2 supplies mask with kernel enabled CPU features, so that
252 * the application can discover that it can safely use them.
253 * The bits are defined in uapi/asm/hwcap2.h.
254 */
255 #define ELF_HWCAP2 (elf_hwcap2)
256
257 /* This yields a string that ld.so will use to load implementation
258 specific libraries for optimization. This is more specific in
259 intent than poking at uname or /proc/cpuinfo.
260
261 For the moment, we have only optimizations for the Intel generations,
262 but that could change... */
263
264 #define SET_PERSONALITY(ex) set_personality_64bit()
265
266 /*
267 * An executable for which elf_read_implies_exec() returns TRUE will
268 * have the READ_IMPLIES_EXEC personality flag set automatically.
269 *
270 * The decision process for determining the results are:
271 *
272 * CPU: | lacks NX* | has NX, ia32 | has NX, x86_64 |
273 * ELF: | | | |
274 * ---------------------|------------|------------------|----------------|
275 * missing PT_GNU_STACK | exec-all | exec-all | exec-none |
276 * PT_GNU_STACK == RWX | exec-stack | exec-stack | exec-stack |
277 * PT_GNU_STACK == RW | exec-none | exec-none | exec-none |
278 *
279 * exec-all : all PROT_READ user mappings are executable, except when
280 * backed by files on a noexec-filesystem.
281 * exec-none : only PROT_EXEC user mappings are executable.
282 * exec-stack: only the stack and PROT_EXEC user mappings are executable.
283 *
284 * *this column has no architectural effect: NX markings are ignored by
285 * hardware, but may have behavioral effects when "wants X" collides with
286 * "cannot be X" constraints in memory permission flags, as in
287 * https://lkml.kernel.org/r/20190418055759.GA3155@mellanox.com
288 *
289 */
290 #define elf_read_implies_exec(ex, executable_stack) \
291 (mmap_is_ia32() && executable_stack == EXSTACK_DEFAULT)
292
293 struct task_struct;
294
295 #define ARCH_DLINFO_IA32 \
296 do { \
297 if (VDSO_CURRENT_BASE) { \
298 NEW_AUX_ENT(AT_SYSINFO, VDSO_ENTRY); \
299 NEW_AUX_ENT(AT_SYSINFO_EHDR, VDSO_CURRENT_BASE); \
300 } \
301 NEW_AUX_ENT(AT_MINSIGSTKSZ, get_sigframe_size()); \
302 } while (0)
303
304 /*
305 * True on X86_32 or when emulating IA32 on X86_64
306 */
mmap_is_ia32(void)307 static inline int mmap_is_ia32(void)
308 {
309 return IS_ENABLED(CONFIG_X86_32) ||
310 (IS_ENABLED(CONFIG_COMPAT) &&
311 test_thread_flag(TIF_ADDR32));
312 }
313
314 extern unsigned long task_size_32bit(void);
315 extern unsigned long task_size_64bit(int full_addr_space);
316 extern unsigned long get_mmap_base(int is_legacy);
317 extern bool mmap_address_hint_valid(unsigned long addr, unsigned long len);
318 extern unsigned long get_sigframe_size(void);
319
320 #ifdef CONFIG_X86_32
321
322 #define __STACK_RND_MASK(is32bit) (0x7ff)
323 #define STACK_RND_MASK (0x7ff)
324
325 #define ARCH_DLINFO ARCH_DLINFO_IA32
326
327 /* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
328
329 #else /* CONFIG_X86_32 */
330
331 /* 1GB for 64bit, 8MB for 32bit */
332 #define __STACK_RND_MASK(is32bit) ((is32bit) ? 0x7ff : 0x3fffff)
333 #define STACK_RND_MASK __STACK_RND_MASK(mmap_is_ia32())
334
335 #define ARCH_DLINFO \
336 do { \
337 if (vdso64_enabled) \
338 NEW_AUX_ENT(AT_SYSINFO_EHDR, \
339 (unsigned long __force)current->mm->context.vdso); \
340 NEW_AUX_ENT(AT_MINSIGSTKSZ, get_sigframe_size()); \
341 } while (0)
342
343 /* As a historical oddity, the x32 and x86_64 vDSOs are controlled together. */
344 #define ARCH_DLINFO_X32 \
345 do { \
346 if (vdso64_enabled) \
347 NEW_AUX_ENT(AT_SYSINFO_EHDR, \
348 (unsigned long __force)current->mm->context.vdso); \
349 NEW_AUX_ENT(AT_MINSIGSTKSZ, get_sigframe_size()); \
350 } while (0)
351
352 #define AT_SYSINFO 32
353
354 #define COMPAT_ARCH_DLINFO \
355 if (exec->e_machine == EM_X86_64) \
356 ARCH_DLINFO_X32; \
357 else if (IS_ENABLED(CONFIG_IA32_EMULATION)) \
358 ARCH_DLINFO_IA32
359
360 #define COMPAT_ELF_ET_DYN_BASE (TASK_UNMAPPED_BASE + 0x1000000)
361
362 #endif /* !CONFIG_X86_32 */
363
364 #define VDSO_CURRENT_BASE ((unsigned long)current->mm->context.vdso)
365
366 #define VDSO_ENTRY \
367 ((unsigned long)current->mm->context.vdso + \
368 vdso_image_32.sym___kernel_vsyscall)
369
370 struct linux_binprm;
371
372 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
373 extern int arch_setup_additional_pages(struct linux_binprm *bprm,
374 int uses_interp);
375 extern int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
376 int uses_interp, bool x32);
377 #define COMPAT_ARCH_SETUP_ADDITIONAL_PAGES(bprm, ex, interpreter) \
378 compat_arch_setup_additional_pages(bprm, interpreter, \
379 (ex->e_machine == EM_X86_64))
380
381 extern bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs);
382
383 /* Do not change the values. See get_align_mask() */
384 enum align_flags {
385 ALIGN_VA_32 = BIT(0),
386 ALIGN_VA_64 = BIT(1),
387 };
388
389 struct va_alignment {
390 int flags;
391 unsigned long mask;
392 unsigned long bits;
393 } ____cacheline_aligned;
394
395 extern struct va_alignment va_align;
396 #endif /* _ASM_X86_ELF_H */
397